Field of the Invention
The invention relates to a sight including an erector lens and especially a sight with an erector lens seat tightly fitted in a cylinder by an elastic member.
Description of the Related Art
The optical sights used in shooting weapons usually include erector lenses, which transform the image formed in the optical system into an upright image for users' ease of watching. The erector lens is disposed in a cylinder of the sight with a lens seat, and the fitting process of the lens seat into the cylinder could result in an aiming reticule jittering or parallax problem in case of a gap between the lens seat and the cylinder. Therefore, the fitting tolerances between the lens seat and the cylinder and tolerance control on each part are very critical. In order to tightly fit the erector lens sea into the cylinder, the machine tool and grinding process are usually used and combined with stringent tolerance control or real part assembly check, and the manufacturing cost is raised as a burden on both producer and buyer. In addition, the metallic material for making the lens seat causes another relatively higher cost.